title: Down-regulation of keratin 4 and keratin 13 expression in oral squamous cell carcinoma and epithelial dysplasia: a clue for histopathogenesis.
abstract: OBJECTIVE
  This study aimed to identify relevant keratin subtypes that may associate with the pathogenesis of oral epithelial neoplasms.
  
  
  RESULTS
  Expression of all the keratin subtypes was examined by cDNA microarray analysis of 43 oral squamous cell carcinoma (OSCC) cases. Immunohistochemical expression of the major keratins was examined in 100 OSCC and oral epithelial dysplasia (OED) cases. Many changes in keratin expression were observed and, significantly, consistent down-regulation of keratin 4 (K4) and K13 expression was observed. Aberrant expression of K4 and K13 was associated with morphological changes in the affected oral epithelium. Experiments with cell cultures transfected with various keratin subtypes suggested that alterations in keratin subtype expression can cause changes in cell shape and movement.
  
  
  CONCLUSIONS
  Aberrant expression of K4 and K13, which are the dominant pair of differentiation-related keratins in oral keratinocytes, indicates dysregulation of epithelial differentiation in OSCC and OED. These keratins, especially K4, may be useful for pathological diagnosis. We propose that the aberrant expression of K4 and K13 and concomitant up-regulation of the other keratins may be one of the causative factors for morphological alterations in the affected epithelium.
authors.affiliation: Section of Oral Pathology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. s-kei.mpa@tmd.ac.jp
authors.forename: Kei
authors.initials: K
authors.lastname: Sakamoto
authors.forename: Tadanobu
authors.initials: T
authors.lastname: Aragaki
authors.forename: Kei-ichi
authors.initials: K
authors.lastname: Morita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawachi
authors.forename: Kou
authors.initials: K
authors.lastname: Kayamori
authors.forename: Shoichi
authors.initials: S
authors.lastname: Nakanishi
authors.forename: Ken
authors.initials: K
authors.lastname: Omura
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Miki
authors.forename: Norihiko
authors.initials: N
authors.lastname: Okada
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Katsube
authors.forename: Toichiro
authors.initials: T
authors.lastname: Takizawa
authors.forename: Akira
authors.initials: A
authors.lastname: Yamaguchi
mesh_terms: D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000473:pathology*; D002460:Cell Line; D003001:Cloning, Molecular; D015536:Down-Regulation / Q000235:genetics; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D053535:Keratin-13 / Q000235:genetics* / Q000378:metabolism; D053527:Keratin-4 / Q000235:genetics* / Q000378:metabolism; D008297:Male; D009061:Mouth Mucosa / Q000473:pathology*; D009062:Mouth Neoplasms / Q000235:genetics / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis
chemical_list: D053535:Keratin-13; D053527:Keratin-4